/*
 * Copyright (C) 2011 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.support.v4.util;

import android.util.Log;

import java.io.Writer;

/**
 * Helper for accessing features in {@link android.util.LogWriter} introduced
 * after API level 4 in a backwards compatible fashion.
 * 
 * @hide
 */
public class LogWriter extends Writer {
	private final String mTag;
	private StringBuilder mBuilder = new StringBuilder(128);

	/**
	 * Create a new Writer that sends to the log with the given priority and
	 * tag.
	 * 
	 * @param tag
	 *            A string tag to associate with each printed log statement.
	 */
	public LogWriter(String tag) {
		mTag = tag;
	}

	@Override
	public void close() {
		flushBuilder();
	}

	@Override
	public void flush() {
		flushBuilder();
	}

	@Override
	public void write(char[] buf, int offset, int count) {
		for (int i = 0; i < count; i++) {
			char c = buf[offset + i];
			if (c == '\n') {
				flushBuilder();
			} else {
				mBuilder.append(c);
			}
		}
	}

	private void flushBuilder() {
		if (mBuilder.length() > 0) {
			Log.d(mTag, mBuilder.toString());
			mBuilder.delete(0, mBuilder.length());
		}
	}
}
